HSavage bug in Postgresql beta?

Started by Chris Bitmeadover 26 years ago3 messages
#1Chris Bitmead
chris.bitmead@bigfoot.com

I'm using the 990329 snap shot.

I was doing this query...
SELECT story.approved, story.oid FROM story, webuser, category* WHERE
story.webuser = webuser.oid AND story.category = category.oid;
approved| oid
--------+------
f |181760
t |179383
t |179384
t |179385
t |179386
t |179387
(6 rows)

So far, so good. "approved" is a boolean field. Now I try...

SELECT story.approved, story.oid FROM story, webuser, category* WHERE
story.webuser = webuser.oid AND story.category = category.oid and
approved;
approved|oid
--------+---
(0 rows)

Yow! I expect 5 of the above 6 rows, but now I get none!
I tried simplifying the SELECT to only join 2 of the above tables but
the problem didn't arise.

Has anything been fixed recently that might account for this? If not, is
there anyway I can help you guys to get it fixed?

#2Tom Lane
tgl@sss.pgh.pa.us
In reply to: Chris Bitmead (#1)
Re: [HACKERS] HSavage bug in Postgresql beta?

Chris Bitmead <chris.bitmead@bigfoot.com> writes:

SELECT story.approved, story.oid FROM story, webuser, category* WHERE
story.webuser = webuser.oid AND story.category = category.oid and
approved;
[ fails to find tuples it should find ]

Youch. I could not duplicate that here on a toy example, which may
mean there is a recently-fixed bug, or it may just mean that there
are additional conditions required to trigger the bug.

What does EXPLAIN say about the plans used for the two queries?

regards, tom lane

#3Chris Bitmead
chris.bitmead@bigfoot.com
In reply to: Tom Lane (#2)
Re: [HACKERS] HSavage bug in Postgresql beta?

Well I destroyed the database and recreated it, and the problem didn't
happen any more. So unfortunately I can't reproduce it now.

I can tell you that the "approved" field that was causing the problem
was added with an ALTER TABLE ADD COLUMN statement. That's the most
"unusual" thing about the situation. Maybe I'll just have to put it down
to an aberation :-()

Tom Lane wrote:

Show quoted text

Chris Bitmead <chris.bitmead@bigfoot.com> writes:

SELECT story.approved, story.oid FROM story, webuser, category* WHERE
story.webuser = webuser.oid AND story.category = category.oid and
approved;
[ fails to find tuples it should find ]

Youch. I could not duplicate that here on a toy example, which may
mean there is a recently-fixed bug, or it may just mean that there
are additional conditions required to trigger the bug.

What does EXPLAIN say about the plans used for the two queries?

regards, tom lane